This invention relates to a stair structure, and more particularly to a structure of a flight of stair steps which include separate structural members for easy assembly and construction.
According to conventional stair structures of iron or steel framed construction or other known stair structures installed for usual or permanent use, all of which are installed inside or outside the building or house, the separate structural members of specified dimensions are welded at the location where the stairs are assembled and built into a finished stair structure, or else all the individual step members are previously completed at the manufacturing plant and are assembled at their location into a finished stair structure. When a stair structure is completed by welding all its separate members, there are disadvantages which include the increased amount of work for welding the members at their location, the difficulty of securing the necessary manpower to engage in the welding work, the unreliable welded spots of the assembled members, and the extremely limited acceptability of using fire in some surroundings where a stair structure is installed. These disadvantages limit the time and area for building or installing a stair structure. When a stair structure is built by assembling all the previously completed step members at their final location, the use of cranes or other large-scale machines are involved. In this case, there are also limitations to installing a stair structure inside a completed building, since it is difficult or impossible to move the individual step members and other structural members into the building which has been completed. This means that the time at which the installation work should begin is extremely limited. Other disadvantages include the limitations include working area and manpower.